NL1042368B1 - Prosthesis for a temporomandibular joint - Google Patents

Abstract

Prosthesis for the mandibular side of a temporamandibular joint, comprising a head part replacing the condylar head, in particular at the anatomical location, and one. mounting plate, the mounting plate being saddle-shaped with a lateral portion and a medial portion formed and intended to abut on either side of the rising branch of the lower jaw, directly below the arcuate recess in the upper end of the rising branch of the lower jaw lie.

Description

NL 1042368

Prosthesis for a temporoandibular joint

BACKGROUND OF THE INVENTION

The invention relates to a jaw joint prosthesis, or prosthesis replacing a tampophoboidal joint (TMG).

In a jaw joint and its surroundings, the connecting area of the lower jaw (mandtbula) and the sleeping leg (os temporal), in particular, of the lower jaw, the processus condylaris, with neck and (jaw) head (caput mandibula) can be distinguished. , and of the sleeping bone, the joint cup (fossa gienoidalis), formed behind the julboeg (arcus zygomaticus), with these interconnecting muscle and connective tissues and the joint disc (discus articularis).

Patients with significant jaw joint damage due to ankylosis, rheumatoid arthritis, bone arthritis, tumors and trauma suffer from chewing and speech problems. To remedy these problems, partial or complete replacement of the jaw joint may be required.

U.S. Patent 3,178,728 discloses a one-sided prosthesis. This is formed by a chromium-cobalt casting for covering the joint cup, including the anterior “bone nodule” (tuberculum articulare), to provide a bearing for the jaw head. A comparable but shorter one-sided prosthesis is known from US patent 3,579,643. This prosthesis releases the glenoidal cavity. A more recent proposal is described in Uf 2009/0222102.

Double-sided prostheses are known from, inter alia, US patents 4,693,722, 4,778,472, 4,917,701, 5,549,680, 5,989,292 and FR patent application 2,558,721.

A more recent design of a double-sided prosthesis is the subject of US patent 6,132,466, including a replacement for the jaw head and a bearing therefor. The jaw head prosthesis comprises a downwardly extending strip for mounting by means of screws on and below the neck of the processus. condyfaris. A similar design is the subject of US patent application 2019/0138092.

Another two-sided prosthesis is known from WO 2014/023903, wherein the part for replacing the jaw head is two-part, with a faintly bent pin for the prosthesis jaw head to be fixed in the jaw and a holder part which comprises a downwardly extending strip for attachment by by means of screws on and below the neck of the condylaris process and a holder ring formed as a whole for holding the pin in the correct orientation.

SUMMARY OF THE INVENTION

An object of the invention is to provide a prosthesis for a jaw head in a temporomandibular joint, which in many cases can be fitted with less risk for the patient.

An object of the invention is to provide a prosthesis for a jaw head in a temporomandibular joint, which in many cases can be fitted with less effort.

An object of the invention is to provide a bilateral prosthesis for a temporomandibular joint.

From one aspect, the invention provides a prosthesis for the mandibular side of a temporomandibular joint, comprising a head portion replacing the condylar joint. at the anatomical location and a mounting plate for attachment to the lower jaw, the mounting plate being formed with a lateral portion formed and intended for abutment against the lateral side of the rising branch of the lower jaw, directly below the arcuate recess (incisura semilunaris) in the upper end of the rising branch of the lower jaw, wherein the lateral portion is provided with holes for attachment to the lateral side of the rising branch of the lower jaw and wherein the mounting plate comprises an upper portion integral with the lateral portion and formed and is designed for abutment on the concave upper edge of the bend-shaped recess in the upper end of the rising branch of the lower jaw.

Hereby a displacement of the locations and transfer of the forces exerted on the jaw head, which is situated at a location corresponding to the anatomical location, to the lower jaw can be realized, from the areas known below the condylar neck in the prior art, often near the jaw angle, higher and more forward areas on the rising branch of the lower jaw, on the upper edge of the arc-shaped mandibular recess and below that on the literate side of the rising branch of the lower jaw. By moving the attachment area to the rising branch of the lower jaw, the area at the jaw angle can be left untouched when placing the prosthesis, because the vertical downward extension can remain limited, so that also outside the area of the buccal branch of the facial can remain nerve. Vertical forces need only be transmitted via shear-loaded bone screws, but can also be transmitted to the lower jaw via the bearing on the naturally provided arcuate upper edge of said recess. The abutment in the vertical direction and in the medial direction against respectively the upper edge of the arcuate recess and the lateral side of the lower jaw can facilitate the placement,

In a further development thereof, the fastening plate comprises a medial portion that is integral with the lateral portion and the upper portion, and is formed and intended to abut against the medial side of the rising branch of the lower jaw, preferably right below the arcuate recess in the upper end of the rising branch of the lower jaw. This promotes stability in the right direction. Furthermore, the placement of the prosthesis is facilitated. in a further development, the upper part, viewed in a direction parallel to dorsai-ventral, at least partly concave, is formed with the cavity upwards.

From another aspect, the invention provides a mandible for a mandible side of a temporomandibular joint, comprising a head portion replacing the jaw head at the anatomical location and a mounting plate, the mounting plate comprising a lateral section and a medial section formed and formed. are intended to abut on either side of the rising branch of the lower jaw, directly below the arcuate recess in the upper end of the rising branch of the lower jaw, and with an integral upper part thereof, that concave, with the cavity upwards, is formed viewed in a direction transverse to the lateral portion and concave, with the cavity down, is formed viewed in a cross section. In one embodiment, the mounting plate has the appearance of a horse saddle, rather than the appearance of the hyperbolic piraboioid. The mounting plate may have a double concave shape, with both concave shapes facing opposite (up and down!) And rotated about 90 degrees relative to each other.

In one embodiment, only the lateral portion is provided with bollards for attachment to the lateral side of the rising branch of the lower jaw.

Dorsal, ventral, lateral, medial, up, down * underde et cetera point to the position in use condition placed in a standing patient.

As noted, the extension of the lateral portion / flange can remain limited in the downward direction, in particular the lateral portion in a direction parallel to the direction of projection of the head portion can have a length that is less than its length in a (venous -dorsal) direction transverse thereto.

The shape of the lateral portion or lateral wing will be aligned with the anatomy of the bone. The lateral portion may, for example, be sickle-shaped, for example comprise an L-shaped lip, or comprise multiple lips, for example one lip near the condylar neck and one lip near the coronoid protrusion. This is not an exhaustive list, other forms are also possible.

The shape of the medial portion or medial wing will be aligned with the anatomy of the bone. The medial portion can form with the upper portion an overhanging edge abutting the bone. The medial portion can be, for example, sickle-shaped, for example comprise an L-shaped lip, or comprise several lips, for example one lip near the condylar neck and one lip near the coronoid protrusion. This is not an exhaustive list, other forms are also possible.

The upper portion may be continuous in comb direction or may comprise multiple portions, in that. interrupted. The length in comb alignment may be in the order of magnitude of the spacing of the necks of both protrusions, or a fraction (e.g. Yz, 1/3) thereof.

In one development, the lateral portion is designed to extend, in the deployed state, in the ventral direction beyond the lowest point of cj® arcuate upper edge, thus into the region directly below the portion of said upper edge that is ascending in the ventral direction (to the coronoid protrusion).

In one development, the upper portion is arranged to extend in the ventral direction in the placed state beyond the lowest point of the arcuate upper edge, thus to the region of said upper edge that rises in the ventral direction (toward the coronoid protrusion).

In a winding, the medial portion is designed to extend, in the placed state, in the ventral direction beyond the lowest point of the arcuate upper edge, that is to say, in the region that is directly below the portion of said upper edge that rises in the ventral direction ( coronoid protrusion). if desired, the lateral portion may be formed and intended to extend to the coronoid protrusion. This may, for example, be desirable in connection with the number of screws to be installed. The extension in the frontal direction does not cause a conflict with nerve bundles. The midial portion may also be formed and intended to extend to the coronoid branch. The medial portion can remain free of the sphenomandibular ligament.

There is also room for the upper portion, and this may be shaped and intended to extend to the coronoid protrusion. in one embodiment the head part and the mounting plate form one jelly! May each other.

The prosthesis can be made in alignment with the affected patient. The shape and condition of the rising branch of the lower jaw, in particular the coronoid protrusion thereof and the condylar neck, can be determined by scanning. Based on this, the optimal prosthesis can be designed for that patient and recorded in a CAD file. With that file, a computer-controlled device can make the prosthesis, in a machining operation such as milling, or in an additive production technique such as injection molding, laser sintering, stereolithography, in particular FDM, SLM, SLS or another 3D printing technique, for example of titanium or PEEK (polyether-ether-ketone). The jaw head can be provided with a titanium-nitride layer or a thin ceramic layer.

From a further aspect, the invention provides for one system of a prosthesis according to the invention and one prosthesis for the glenoidal fossa of the head part. The lower part allows both rotation of the jaw head about the medial-lateral axis and translation thereof in anterior posterior (ventral-dorsal) direction, according to a natural situation.

From a further aspect, the invention provides in a method for replacing the jaw head in a patient with a prosthesis therefor, wherein the shape of the edge of the arcuate recess in the upper end of the rising branch of the lower jaw is determined and partly based on the prosthesis according to the invention thereof is designed and manufactured, whereafter the prosthesis is placed on the relevant rising branch of the lower jaw.

It is noted that a double-sided TMG prosthesis is known from JP H 11 146889, in which in an embodiment in which the condylar head is replaced at the anatomical location and the attachment on the lateral side of the rising branch of the lower jaw takes place with a fastening strip which extends to reaches into the area of the jaw angle.

U.S. Pat. No. 4,726,808 discloses a mandibular component with a prosthetic head of a TMG, which is provided with two fastening strips to be attached to the lateral and medial side of the rising branch of the lower jaw, which extend into the region of reach the lower jaw, while releasing the edge of the (semisunar incisura).

The aspects and measures described in this description and claims of the application and / or shown in the drawings of this application can, where possible, also be applied separately from each other. These individual aspects can be the subject of split-off patent applications that are aimed at this. This applies in particular to the measures and aspects that are described per se in the reference claims

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be elucidated on the basis of an exemplary embodiment shown in the accompanying drawings. The views are named from the relevant side, so a lateral view is a view from the lateral side. Shown is:

Figures 1A-E respectively a medial side view, a lateral side view, a postera-lateral view, a postera-medial view and a cross-sectional view according to plane IE in figure 1B on the mandibular component of a jaw joint prosthesis for placement on a lower jaw;

Figures 2A and 2B show respectively a postera-lateral view and a postera-medial view of a fossa component of a jaw joint prosthesis for placement on an upper jaw;

Figures 3A and 3B show a postera-lateral view and a posterl-media view of an assembly of the mandibular component of Figures 1A-E and the fossa component of Figures 2A, B; and

Figures 4A and 4B show a lateral and a median side view, respectively, of an assembly according to the invention in the placed state.

DETAILED DESCRIPTION OF THE DRAWINGS

Figures 1A-D show the mandibular component 1 of a temporomandular joint prosthesis ('IMG prosthesis), which comprises a lateral wing 3 and a medial wing 4, which are connected to each other by an integral part thereof or comb 5. The lateral wing 3 is provided with bone screw holes 6. It can clearly be seen that the component 1 is saddle-shaped, U-shaped in ventral and dorsal view and side view (seen transversely of the lateral part, see figure 1E), U-shaped, The mounting plate here has a double concave shape, with both concave shapes facing in the opposite direction (up and down! and rotated about 90 degrees relative to each other. The mounting plate also means the occurrence of a hyperbolic paraboloid.

An artificial jaw head 2 protrudes upwards as a kind of saddle button at the rear end via a neck 8. In figure 1C the rear edges 1a and 4a of both wings are indicated. As can be seen in figures 1A and 1C, a downwardly extending pin 7 is provided within the component 1 at the rear end, which pin remains spaced apart from both wings 3 and 4. This pin 7 is optional! and may be provided as an irrarnatory pen.

The mandibular component is made entirely from titanium or tantalum, for example, or from an alloy thereof, from PEEK or UHMWPE, or a composition of these or other materials, preferably manufactured with additive manufacturing and / or CNC robotic milling.

The mandibular component is designed and manufactured in alignment with the shape and condition of the rising branch of the lower jaw of the patient in question, such that both wings fit flush with the rising branch of the lower jaw, with the artificial jaw head 2 the condylar head on the anatomical location, and the upper part is fittingly against the upper edge of the semisunaris incisura.

The medial wing can be shaped differently depending on the circumstances, for example be narrower, be L-shaped, or consist of several lips, for example one lip near the condyle neck and one lip near the coronoid protrusion.

The lateral wing may be shaped differently depending on the circumstances, for example be narrower, be L-shaped, or be made of several lips, for example one lip near the eondyiaar neck and one lip near the coronoid protrusion.

Furthermore, the upper part can be interrupted in combing direction instead of continuously - as depicted in figures 1A-D -.

In Figures 2A and 2B, a temporal side fossa component 10 for a jaw joint prosthesis is disposed, which can interact with the mandibular component 1. The fossa component 10 forms an elongated, downward-opening bowl 11 in which the artificial jaw cup 2 can rotate and can slide, as much as possible in accordance with a natural jaw joint. For fixing in the skull base of a patient, bifscrew holes 12 are provided.

The fossa component can be manufactured, optionally as a whole, from titanium or tantalum, or whey from an alloy thereof, from PEEK or UHMWPE, or a composition of these or other materials, preferably manufactured with additive manufacturing and / or CNC robotic milling. In one embodiment, the portion with the holes 12 is made of metal, the portion of the bowl 11 is from UHMWPE. The downwardly facing bearing surface has a horizontal lip 14 at the front end and vertical lips 13 at the rear end and on the medial side to prevent luxation and reankylosis.

The fossa component is designed and manufactured in alignment with the shape and condition of the yoke arch and the joint socket, including the joint lump (tuberculum articularis, and in alignment with the mandibular component.

In figures 4A and 4B a left lower jaw is 100, with the rising branch 101 (ramus mandibuiae), the coroinoid process 102 and the condylarus 103 process. via a concave ridge / ridge or upper edge 104, which delimits the incisura semilunaris 105 downwards, into the coroinoid processus 102. Line 107 still indicates the lower edge of the fossa infratemporalis.

After preparatory actions, such as surgical resection of the diseased jaw head (part) and after the area has been made accessible by an incision at the level of the sleeping area (leaving the area of the jaw angle 106 virtually unaffected), the mandibular component 1 as if it were a saddle, with the upper part 5 resting on the concave comb / ridge 104 and the two wings 3 and 4 on either side, abutting against both sides of the lower jaw. As seen in Figure 4A, the height h of the lateral wing 3 relative to the lowest point M of the comb is about half or less of the height of the rising branch of the lower jaw 101, and the wing I remains above the buccal branch of the facial nerve. Furthermore, it can be seen that the component 1 in the forward direction extends well beyond the position M of the lowest point of the comb / ridge 104. The "saddle" 1 is fixed by means of bone screws in the holes 6 in the lateral wing 3 on the rising branch 101, in the upper half thereof.

The fossa component 10 is also placed and fixed with bone screws in holes 12 on the sleeping bone 110 (os temporal).

With the saddle-shaped jaw-head prosthesis according to the invention, adjacent contact with the bone is provided on either side of the rising branch of the lower jaw, which is favorable for the stability and the ingrowth of bone tissue. The risk of releasing the prosthesis is therefore considerably reduced! limited.

The chewing forces are absorbed by the prosthesis 1 and by this spread over behavior on the lower jaw, namely on the condyle stump of the rising branch, by pressure on the comb / ridge and by transverse forces on the bone screws on the lateral side.

The relatively large surface of the lateral wing increases the freedom of choice in number and location of the holes for the bone screws,

In one embodiment, no medial wing is present in the mandibular component. The upper part or comb {which is Concave in cross-section with the cavity turned downwards, then extends / rests on the upper edge / direction / bone The medial wing can also be short, viewed downwards, for example in the form of an edge just over the upper edge / guide / bone extends, so that the appearance of a hook is obtained in cross-section.

The inventions are in no way limited to the embodiments shown and described in the drawings and description. The above description is included to illustrate the operation of preferred embodiments of the invention, and not to limit the scope of the invention. Starting from the above explanation, many variations will be apparent to those skilled in the art that fall within the spirit and scope of the present invention. Variations are possible of the parts shown in the drawings and described in the description. They can be used separately in other embodiments of the invention (s). Components of various examples given can be combined with each other.

Claims (18)

1. Prosthesis for the mandibular side of a temporomandibular joint, comprising a head part for replacing the jaw head, in particular at the anatomical location, and a mounting plate for mounting on the lower jaw, the mounting plate being formed with a lateral portion formed and is intended for abutment against the lateral side of the rising branch of the lower jaw, directly below the arcuate recess in the upper end of the rising branch of the lower jaw, the lateral portion being provided with holes for mounting on the lateral side of the rising branch of the lower jaw, wherein the mounting plate comprises an upper portion which is integral with the lateral portion and is shaped and intended to abut on the concave upper edge of the arcuate recess in the upper end of the Rising branch of the lower jaw. A prosthesis according to claim 1, wherein the attachment plate comprises a medial portion integral with the lateral portion and upper portion, and formed and intended for abutment against the medial side of the rising branch of the lower jaw, preferably directly below the arcuate recess in the upper end of the rising branch of the lower jaw. 3. Prosthesis for the mandibular side of a temporomandibular joint, comprising a head part replacing the jaw head, in particular at the anatomical location, and a fixing plate, the fixing plate comprising a lateral part and a medical part formed and intended to to lie on either side of the rising branch of the lower jaw, directly below the arcuate recess in the upper end of the rising branch of the lower jaw, and with a corresponding one. forming upper portion, which is concave with the cavity facing upwards, viewed in a direction transverse to the lateral portion, and concavely, with the cavity facing downwards, viewed in cross-section. A prosthesis according to any one of the preceding claims, wherein only the lateral portion is provided with holes for attachment to the lateral side of the rising branch of the lower jaw. The prosthesis of any one of the preceding claims, wherein the lateral portion in a direction parallel to the direction of protrusion of the head portion has a length that is less than its length in a direction transverse thereto. A prosthesis according to any one of the preceding claims, wherein the lateral portion is sickle-shaped. Ψ. A prosthesis according to any one of claims 2-6, when dependent vg | claim 2 or 3, wherein the medial portion is goofy. A prosthesis according to any one of the preceding claims, wherein the lateral portion is designed to extend, in the placed state, in the ventral direction beyond the lowest point of the arcuate upper edge, thus into the region lying directly below the portion of said upper edge which is rising in the ventral direction (in the direction of the coronoid protrusion). A prosthesis according to any one of the preceding claims, wherein the upper part is designed to extend, in the placed state, in the ventral direction beyond the lowest point of the arcuate upper edge, that is to say in the region of said upper edge which is rising in the ventral direction1 (in the direction of the coronoid protrusion). A prosthesis according to any one of claims 2 to 9, when dependent on claim 2 or 3, wherein the medial portion is designed to extend in the vented direction in vented direction beyond the lowest point of the arcuate upper edge, thus into the region that is directly below the portion of said upper edge that rises in ventraie direction (in the direction of the coronoid protrusion). A prosthesis according to any one of the preceding claims, wherein the lateral portion is formed and intended to extend onto the coronoid branch. The prosthesis of any one of claims 2-11 when dependent on claim 2 or 3, wherein the medial root is formed and intended to extend to the coronoid branch. A prosthesis according to any one of the preceding claims, wherein the upper portion is formed and intended to extend onto the coronoid branch. 14. A prosthesis according to any one of the preceding claims, wherein the head part and the fixing plate are integral with each other. A prosthesis according to any one of the preceding claims, provided with a pin extending downwardly from the jaw head for intramedullary attachment in the coronoid neck. A prosthesis according to any one of claims 2-15 when dependent on claim 2 or I, wherein the attachment plate has the appearance of a saddle, in particular the occurrence of a hyperbolic paraboloid. 17. Assembly of a prosthesis according to any one of the preceding claims and a prosthesis for the glenoidalis fossa (jawbone cup) as a bearing part for the head part. A method for replacing the jaw head in a patient with a prosthesis therefor, wherein the shape of the edge of the arcuate recess in the upper end of the rising branch of the lower jaw is determined and partly on the basis thereof the prosthesis according to one of the claims 1-16 is designed and manufactured, after which the prosthesis is placed on the relevant rising branch of the lower jaw. 19. Prosthesis for a jaw head, provided with one or more of the characterizing measures described in the attached description and / or shown in the attached drawings. Assembly of a prosthesis according to one of the preceding claims and a prosthesis for the glenoidal fossa as bearing part for the head part provided with one or more of the characterizing measures described in the attached description and / or shown in the attached drawings. 21 Method provided with one or more of the characterizing measures described in the attached description and / or shown in the attached drawings. -Q-O-O-O-O-O-O-